(The Restitution of Christianity)

by

Michael Servetus

1553

The whole apostolic church is summoned to the threshold. Once again there is restored knowledge of God, of the faith of Christ our justification, of the regeneration of baptism, and of participation in the Lord’s Supper. And 
finally with the heavenly kingdom restored to us, the wicked captivity in Babylon has been ended and antichrist with his host destroyed.

And at that time shall Michael stand up.

And war broke out in heaven.

[Vienne]

{The following is Servetus' postulation of the secondary circulation of the blood. He is credited with being the first to publish this discovery! It was found in his final book, Christianismi restitutio} 

Not only because such gifts, but by reason of that one alone who breathes the divine spirit into us, God is said to give us his spirit, Gen. 2 and 6. Our soul is a kind of lantern of God, Prov. 20. It is like a spark of the spirit of God, a reflection of the wisdom of God, created yet very similar to that spiritual wisdom, incorporated in it, retaining the innate light of divinity, the spark of that prime wisdom and the very spirit of divinity. God himself testifies, in chapter 6 above, that the spirit of divinity was innate in man even after Adam's sin. The dispensation of our life is given and is sustained through grace from his breathe, as Job says, chap. 10 and 32 and following. God breathed the divine spirit into Adam's nostrils together with a breath of air, and thence it remains, Isaiah 2 and Psa. 103. God himself maintains the breath of life for us by his spirit, giving breath to the people who are upon the earth and spirit to those treading it, so that we live, move and exist in him, Isaiah 42 and Acts 17. Wind from the four winds and breath from the four breaths gathered by God revive corpses, Ezek. 37. From a breath of air God there introduces the divine spirit into men in whom the life of inspired air was innate. Hence in Hebrew "spirit' is represented in the same way as "breath." From the air God introduces the divine spirit, introducing the air with the spirit itself and the spark of the very deity which fills the air. The saying of Orpheus is true, that the divine spirit is carried by the winds and enters through full inspiration, as Aristotle cites in the books, De anima. Ezekiel teaches that the divine spirit contains a kind of elemental substance and, as God himself teaches, something in the substance of the blood. I shall explain this matter at great length here so that you may thence understand that the substance of the created spirit of Christ is essentially joined to the very substance of the holy spirit. I shall call the air spirit because in the sacred language there is no special name for air. Indeed, that fact indicated that the divine breath is in the air which the spirit of the Lord fills.

So that you, the reader, may have the whole doctrine of the divine spirit and the spirit, I shall add here the divine philosophy which you will easily understand if you have been trained in anatomy. It is said that in us there is a triple spirit from substance of three higher elements, natural, vital and animal. Aphrodisaeus calls them three spirits. But they are not three but once again of the single spirit (spiritus). The vital spirit is that which is communicated through anastomoses from the arteries to the veins in which it is called the natural [spirit]. Therefore the first [i.e., natural spirit] is of the blood, and its seat is in the liver and in the veins of the body. The second is the vital spirit of which the seat is in the heart and the arteries of the body. The third is the animal spirit, a ray of light, as it were, of which the seat is in the brain and the nerves of the body. In all these there resides the energy of the one spirit and of the light of God. The formation of man from the uterus teaches that the vital spirit is communicated from the heart to the liver. For an artery joined to a vein is transmitted through the umbilicus of the foetus, and in like manner afterward the artery and vein are always joined in us. The divine spirit of Adam was inspired from God into the heart before [it was communicated into] the liver, and from there it was communicated to the liver. The divine spirit was truly drawn into the mouth and nostrils, but the inspiration extended to the heart. The heart is the first living thing, the source of heat in the middle of the body. From the liver it takes the liquid of life, a kind of material, and in return vivifies it, just as the liquid water furnishes material for higher substances and by them, with the addition of light, is vivified so that [in turn] it may invigorate. The material of the divine spirit is from the blood of the liver by way of a remarkable elaboration of which you will now hear. Hence it is said that the divine spirit is in the blood, and the divine spirit is itself the blood, or the sanguineous spirit. It is not said that the divine spirit is principally in the walls of the heart, or in the body of the brain or of the liver, but in the blood, as by God himself in Gen. 9, Levit. 7 and Deut. 12.

In this matter there must first be understood the substantial generation of the vital spirit which is composed of a very subtle blood nourished by the inspired air. The vital spirit has its origin in the left ventricle of the heart, and the lungs assist greatly in its generation. It is a rarefied spirit, elaborated by the force of heat, reddish-yellow (flavo) and of firey potency, so that it is a kind of clear vapor from very pure blood, containing in itself the substance of water, air and fire. It is generated in the lungs from a mixture of inspired air with elaborated, subtle blood which the right ventricle of the heart communicates to the left. However, this communication is made not through the middle wall of the heart, as is commonly believed, but by a very ingenious arrangement the subtle blood is urged forward by a long course through the lungs; it is elaborated by the lungs, becomes reddish-yellow and is poured from the pulmonary artery into the pulmonary vein. Then in the pulmonary vein it is mixed with inspired air and through expiration it is cleansed of its sooty vapors. Thus finally the whole mixture, suitably prepared for the production of the vital spirit, is drawn onward from the left ventricle of the heart by diastole.

That the communication and elaboration are accomplished in this way through the lungs we are taught by the different conjunctions and the communication of the pulmonary artery with the pulmonary vein in the lungs. The notable size of the pulmonary artery confirms this; that is, it was not made of such sort or of such size, nor does it emit so great a force of pure blood from the heart itself into the lungs merely for their nourishment; nor would the heart be of such service to the lungs, since at an earlier stage, in the embryo, the lungs, as Galen teaches, are nourished from elsewhere because those little membranes or valvules of the heart are not opened until the time of birth. Therefore that the blood is poured from the heart into the lungs at the very time of birth, and so copiously, is for another purpose. Likewise, not merely air, but air mixed with blood, is sent from the lungs to the heart through the pulmonary vein; therefore the mixture occurs in the lungs. That reddish-yellow color is given to the spirituous blood by the lungs; it is not from the heart.

In the left ventricle of the heart there is no place large enough for so great and copious a mixture, nor for that elaborate imbuing the reddish-yellow color. Finally, that middle wall, since it is lacking in vessels and mechanisms, is not suitable for that communication and elaboration, although something may possibly sweat through. By the same arrangement by which a transfusion of the blood from the portal vein to the vena cava occurs in the liver, so a transfusion of the spirit from the pulmonary artery to the pulmonary vein occurs in the lung. If anyone compares these things with those which Galen wrote in books VI and VII, De usu partium, he will thoroughly understand a truth which was unknown to Galen.

And so that vital spirit is then transfused from the left ventricle of the heart into the arteries of the whole body so that which is more rarefied seeks the higher regions where it is further elaborated, especially in the retiform plexus situated under the base of the brain, and approaching the special seat of the rational soul, the animal spirit begins to be formed from the vital. Again it is more greatly rarefied by the firey force of the mind, elaborated and completed in the very slender vessels or hair-like (capillaribus) arteries which are situated in the choroid plexuses and contain the mind itself. These plexuses penetrates all the inmost parts of the brain, internally girdling the ventricles of the brain, and those vessels, enfolded and woven together as far as the origins of the nerves, serve to introduce in these last the faculties of sensation and of motion. Those vessels in a very remarkable way are woven together very finely, and even if they are called arteries, nevertheless they are the termination of arteries extending through the assistance of the meninges to the origin of the nerves. It is a new kind of vessels. For just as in the transfusion from the veins into the artery, so in the transfusion from the arteries into the nerves there is a new kind of vessels from the tunic of the artery in the meninx, since especially do the meninges preserve their tunics in the nerves. The sensibility of the nerves is not in their soft material, as in the brain. All nerves end in membranous filaments which have the most exquisite sensibility and to which for this reason the spirit is always sent. And from those little vessels of the meninges, or choroid plexuses, as from a source, the clear animal spirit is poured forth like a ray through the nerves into the eyes and other sense organs. By the same route, but in reverse, light images of things causing sensation, coming from without, are sent to the same source, penetrating inwardly, as it were, through the clear medium [i.e., spirit].

From these things it is sufficiently clear that that soft mass of the brain is not properly the seat of the rational soul, since it is cold and lacking in sensation. But it is like a bolster for the aforesaid vessels lest they be broken, and like a custodian of the animal spirit lest it blow away when it must be communicated to the nerves; and it is cold that it may temper that fiery heat contained within the vessels. Hence also it happens that the nerves serve the tunic of the membrane in the internal cavity, which is common to the aforesaid vessels as a faithful guardian of the spirit, and they hold this [away] from the thin meninx just as they hold another from the thick. Also those empty spaces of the ventricles of the brain which puzzle philosophers and physicians contain nothing else but the spirit. But the ventricles were made in the first place like a cloaca for the reception of the purgings from the brain so that they may test the excrementa received there, from which morbid defluxions arise, and provide a passage to the palate and nostrils. And when the ventricles are so filled with pituita that the arteries themselves or the choroid plexuses are immersed in it, then suddenly apoplexy is aroused. If a very noxious humor obstructs a part, and its vapor infects the mind, epilepsy occurs, or another disease, according to the part into which it settles when it has been expelled. Therefore let us say that it is the mind which we clearly perceive to be afflicted. From the immoderate heat of those vessels, or from the inflammation of the meninges, obvious delirium and frenzy occur. Whence from the diseases occurring by reason of site and substance, by force of heat and because of the ingenious construction of the vessels containing it, and from the actions of the mind apparent there, we always conclude that those little vessels must be given first consideration because all the rest serve them and because nerves of sensation are tied to them so that they may receive their force from them. Finally, because we perceive the intellect exerting itself there when, as a result of concentrated thought, those arteries are pulsating as far as the temples. He who has not seen this thing will scarcely understand. Those ventricles were made for a second reason, that a portion of the inspired air penetrating through the ethmoid bones to their empty spaces, attracted by diastole from the vessels of the spirit, may refresh and ventilate the animal spirit contained within and the soul. In those vessels are mind, soul, and fiery spirit requiring constant fanning; otherwise, like an eternal fire which has been covered up, there would be suffication. As in the case of ordinary fire, there is required not only fanning and blowing upon so that it may take fuel from the air, but also that it may discharge its sooty vapors into the air. And just as this is common external fire is bound to a thick earthy body, because of a common dryness and because of a common form of light, so that which has the liquid of the body as its food is blown upon, supported and nourished by the air; thus that fiery spirit and our soul are similarly bound to the body, making one with it and having blood as food; it is blown upon, supported and nourished by the airy spirit through inspiration and expiration, so that there is a double nourishment for it, spiritual and corporeal.

(This was taken from Christianismi Restitutio and Other Writings as translated by Charles Donald O'Malley, printed for the members of "The Classics of Medicine Library." © 1989, pages 201-208. This is the only portion of his final work that is translated into English, as far as I have found to date.)